Improved snag-boat



INVENTOR N.FETF.RS, FHOTO-UTHOGRAPHER. WASMINGTUNl n CA distinti stairsgaat naar,

Letters Patent No. 95,609, dated October 5, 1869.

The Schedule referred to in these Letters Patent and making part of theI, EDWARD M. SHIELD, of Cincinnati, Hamilton lcounty, and State of Ohio,'have invented a new and useful Snag-Boat, of which the followingf is adescription.

Nature amt Objects of the Invention.

This is an improvemeutriu the class of" snaglboats, consisting of a pairof hulls, framed .firmly` together, and having a crib or cradle betweenthem7 upon which the snag, sawyer, or other timber, is drawn, and upon.

. which it is cut into suitable lengths or fragments; and

The irst part of my invention relates to the provisv ion of ahoisting-apparatus, which, being driven by one or more steam-engines,distinct from those by which the boat is propelled, enables the boat tobe handled during the engagement and elevation of the snag.

I The second part of my invention relates to an ar rangement ofhead-booms orbowsprits, havingr ob-v lique sheaves, and a drag-chain,for catching and upending of sunken snags, or other obstructions, ashereinafter set forth.

lThe third part of my invention relates to a device V for elevating thetop of the snag into the buttin'gbeam, and the but end clear of theguards.

The fourth part of my invention relates to a provision of a series ofcrosscut-saws, arranged at convenient distances along that side ofeitherhull nearest to the other one, and each worked by its properengine. situated below deck.

'lhe ifth part of my invention relates to -the provision of two sheavesor chocks, one near to the stein Vof each guard, next to the cradle, forleading-lines' or chains to haul the snag back into the pradIe,preparatory to sawing or-cutting up. v i

The sixth part of my invention consistsin a certain arrangement ofrollers and inclined planes, constituting the cradle proper.

General Dcscripttoa'wtth Reference to the Drawings.

In the accompanying drawings Figure l is a plan ot' my snag-boat.

Figure 2 is a longitudinal section, cut through the cradle, and showingthe starboard hull in elevation, said section being taken at the line XX.

Figure 3 is an end view ofthe larboard boats bow, with a portion of thebutting-beam and derrick.

Figure 4 is a transverse section at the line Y Y, showing portions ofthe two hulls and one of the crosscut-saws, with its engine inelevation.

Figure 5 is an enlarged end'view of the larboard drag-chain boom.

A and A' represent two/precisely similar hulls, of such build as topresent large displacement andtonnage, with shallow draught; in otherwords having nearly vertical sides and tlat bottoms.

The said hulls are framed firmly together, by meansA of suitabletimbers, C D E F, about midships, md a timber, G, called thebutting-beam, which timber passes into both hulls, near their hows, andis irmly bolted to the breast-hooks and side-frames or ribs of thehulls.

The said beam slopes downward and forward, and has a rounded front edge,so as to enable it easily to receive the end of any snag that may bedrawn on to it, and to enable the snag to slide easily backward upon aseries of rollers, H H', 4 which'constitutes the cradle proper.

lInclined planes I, placed between the roller H', assist in elevatingandpassing knots and other projections of the snag over the rollers, anddischarging l the snag over the stern, after having been sawedgintofragments; v

Projecting forward from the bow of each' hull is a boom or bowsprit, B,within which -is mounted an oblique sheave, t, for a drag-chain, K,employed for sweeping the bed ofthe river, to detect the presence .ofsnags or other hidden obstructions, and to upendthe saine; f l c Theends of the saiddrag-chain may be made fast to the bills L, or otheriixed objects upon the boat.

Elected upon the adjacent guards of the twohulls',

a littleah'ead of midships, is the frame M, of a hoisting-apparatus,containing a suitable windlass, N, pro-y pelled by two steam-engines, OO', through the medium of any suitable gearing, P, which may-have asliding shaft, Q, for gearing up or down, according to the power orspeed required.

The hoisting-chain Rmay be either attached to the windlass, or be simplywound around it.

For the purpose of supplying the necessary power,

l provide each hull with a battery of boilers, S, which,

instead of being placed centrally, are located n ear that side of eachhull most distant from the other one, so

as to afford on each hull a clear and unobstructed foreand-aftgangwayfor handling thelines and chains, and operating thecrosscut-saws.

3'and 4, in iig. 1,"show steps or sockets forthe points of a pair ofshears, 5, supported by guys 6 and 7, and

having a. pulley, 8, to carry the hoisting-chain R,when

said chain is required for a dead lift on the snag.

T 1" represent the customary engines for propelling and handling theboat.

U represents a series. of crosscut-sawalocated on one of the hulls,adjacent to the cradle.

Each saw is attached to a bell-crank, V, operated by a pitman, V', froma small steam-cylinder, W,'below decks.` The cables or chains Z Z',employed to-draw in the snag in to the cradle after having 'beendetached from the bed of the river, are carried around inthe sheaves 12, near the Sterns of the hulls, at k'theii` adjacent sides, and arethence carried forwardto the customary Opa/ration.

A. ripple, indicatinga sunken obstruction, being ohserved, thedrag-chainis let out, and the boat headed up-stream, into the ripple,until the tautness of the chain indicates that it has caught theobstruction.

The boat being then still driven forward, npends the snag, enabling thebatting-beam to be brought under the same, and the chain (seedottedline, g. 2,) of the hoisting-apparatus is then putin motion, so asto disengage the snag from the bed of the river, and todraw it backwardon to the rst two rollers H.

NVhen a dead lift is necessary, in order to lilt the root of the snagclear`of the guards, the chain R is taken through the pulley 8 beforebeing engaged around the snag.

The leading-lines Z Z' are (before disengagiung `the hoisting-chain)attached tothe top end of the snag, and, the steam-capstans being put inmotion, the snag is drawn abaft on to the cradle, ready for beingreduced to convenient lengths or fragments bythe cross- 'cut-saws.

v2. The pair of drag-chain booms B, having theoblique sheavesvb,as'andfor tliepurpose designed.

' 3. The provision, in asnag-boat, ofa series of 'cross- `eut-saws, U,at suitable intervals along one of the nearer or adjacent sides of thehulls, and each operated by an independent engine, as set forth.

4. The provision, in this connection, of the derck or shears 5, for thepurpose stated. v

5. The sheaves 1 2, arranged and located as and for the purpose stated.

`6. The arrangement of rollers H and inclined planes I, as described. i

In testimony of which invention, I hereunto set my hand.

E. M. SHIELD. Witnesses:

Gmo. H, KNIGHT, JAMES H. LAYMAN.

